I think it's mostly to deal with all the temporary accounts that start as Spam1234@hotmail.com and then get spammed for years without the user ever going back to them.
I suspect a more reasonable rule is that you have to log in or download email at least once 60 days after creation or the account get's deleted in one year.
I suspect a more reasonable rule is that you have to log in or download email at least once 60 days after creation or the account get's deleted in one year.